Diverless helicopter weapon recovery devices

ABSTRACT

A rigid aluminum framed cage including a barrel, a long tapered skirt, and landing frame adapted to recover by encapsulation a vertical floating exercise torpedo in high sea states upon deployment of the cage from the helicopter. Upon deployment, the skirt provides the required capture area at its large diameter end and the selected taper affords optimum guide to funnel the unit being captured into the barrel upon tipping the cage so that the larger end diameter of the skirt is at a slightly higher elevation than the barrel.

United States Patent 1191 Munro et a1.

1451 Nov. 25, 1975 1 1 DIVERLESS HELICOPTER WEAPON RECOVERY DEVICES [75] Inventors: James M. Munro, North Kingstown,

R.l.; David J. Pimental, South Dartmouth, Mass; David J. Ramstad, Portsmouth, R.I.; John R. Hinves, Somerset, Mass.

[73] Assignee: The United States of America as represented by the Secretary of the Navy, Washington, DC.

[22] Filed: Aug. 30, 1974 [21] Appl. No.: 502,257

[52] U.S. Cl 244/137 R; 9/14; 114/240 R; 294/67 DA [51] Int. Cl. l B64D l/22 [58] Field of Search 244/137 R; 9/14, 9; 114/240 R, 241; 89/l.809, 1.81, l A; 214/] QC, 1 Q, 1 OD, 658; 294/66, 67 R, 67 BA,

67 DA, 67 DB, 78 A [56] References Cited UNITED STATES PATENTS 3,589,765 6/1971 Lematta 294/66 R Hettinger et al. 114/20 R X Ramsey et al. 1 14/241 Primary Examiner-Trygve M. BliX Assistant Examiner-Barry L. Kelmachter Attorney, Agent, or Firm-Richard S. Sciascia; Arthur A. McGill; Prithvi C. Lall [57] ABSTRACT A rigid aluminum framed cage including a barrel, a long tapered skirt, and landing frame adapted to recover by encapsulation a vertical floating exercise torpedo in high sea states upon deployment of the cage from the helicopter. Upon deployment, the skirt provides the required capture area at its large diameter end and the selected taper affords optimum guide to funnel the unit being captured into the barrel upon tipping the cage so that the larger end diameter of the skirt is at a slightly higher elevation than the barrel.

3 Claims, 5 Drawing Figures U.S. Patent Nov. 25, 1975 DIVERLESS HELICOPTER WEAPON RECOVERY DEVICES STATEMENT OF GOVERNMENT INTEREST The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION The present invention generally relates to capture devices and more particular to an improved system for recovering vertical floating exercise torpedoes.

The Navy traditionally has captured and recovered expended torpedoes and torpedo targets through the use of various types of small retriever crafts of medium to high speed. Typical of these small craft is the standard 72 foot I-ISTR torpedo retriever in use at the Atlantic Undersea Test and Evaluation Center. The I-ISTR has an open stem with an inclined plane leading from just above the water line to the storage area amidships. The incline plane contains four tracks with rollers, up which the captured torpedoes are winched much in the manner a small ship is winched up a marine railway. The inclined plane rests between two gunwales, between which there is a narrow catwalk aft bridging the stem to facilitate handling.

The expended torpedo is captured by means of a line and a hook or some type of capture device. The HSTR This lead to a plurality of new capture and recovery systems.

One new approach to the handling problem of the torpedo involved the use of a bell shield dropped over the vertically floating torpedo from an extended boom, articulated crane mounted on the fore deck on one side of the recovery vessel. After the bell shield was in position over approximately two-thirds the length of the torpedo, various types of locking collars or devices were actuated to contain the torpedo within the bell shield. The crane then brought the torpedo to the surface into a horizontal attitude and hoisted it aboard the vessel. There were many mechanical problems with this system, and there still remained a good chance for damage in handling the expended weapons in marginal seas.

Another problem under these conditions was the length of time required to transport the expended weapons back to the shop and landing pad on shore. This provided the problem of additional delay of the turn around of the torpedo. Each torpedo retriever was capable of returning normally four weapons per trip and the transit time from the range to shore by boat was approximately 3 hours. In order to meet the increased demands it was determined that it was necessary to go to helicopter capture and recovery of the weapons and targets.

One such helicopter recovery system consisted of two positioning bands with choker type lifting cables around each band. Each lifting cable was attached to a suspension sling from the helicopter hard lifting point. During the recovery operation the helicopter hovered over the expended weapon and two diver/technicians were deployed into the water with the recovery rig. The bands were installed on the weapon by the divers, and after the divers were retrieved the helicopter ascended and the weapon lifted and transported in the horizontal attitude to the main base. At the main base the landing area for the weapon was a rack or trampoline. Nylon bands were strung across the rack, and it was on these that the helicopter landed the transported weapon. In this procedure the recovery of a horizontal floating weapon was the same as for a vertically floating one.

Although the above system meets certain specific needs and proved the superiority of recovery by helicopte'r over that of small craft retriever from the point of view of decreased chance for physical damage to the weapon and reduced overall transit time for return to the weapon shop for recycling, the fact that the system required diver/technicians in the water for the capture and a specially prepared landing area dictated continuation of a search for an improved method. The search concentrated on a system which did not require a diver in the water and which had a self contained landing apparatus.

SUMMARY OF THE INVENTION According, it is a general purpose and object of the present invention to provide an improved recovery system. It is a further object to provide suchsystem for the recovery of expended exercise torpedoes without the necessity of men in the water to aid in such recovery. Another object is that after recovery a system need not be provided to receive such torpedo upon return to the main base. Additionally, the system must yield speed and efficiency at relatively low cost.

The above is attained in accordance with the present invention by providing a system connected by means of cables or other linking devices to a helicopter. The system is deployed to enclose a torpedo when the torpedo is in a vertical position. The enclosure and torpedo are tilted to a horizontal position for lifting out of the water and transporting to a landing area. The system utilizes a landing frame for protection when the device with its encapsulated torpedo is placed upon the ground.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1 there is shown a recovery system 10 comprising a rigid aluminum framed cage being deployed from a helicopter (not shown) for retrieval of an exercise torpedo 12 in water. The torpedo 12 is in the vertical position with its fore end exposed above the surface of the water. The recovery system has a rescue hoist cable 14 and cargo hook cable 16 both of which are attached to the helicopter. The rescue hoist cable 14 is attached to a cylindrical frame barrel section 18 that has a lifting ring 20 for engaging cable 14. A landing frame 22 and a strong back 24 are both affixed to the cylindrical barrel section 18, with landing frame 22 and strongback 24 being separated from each other by approximately 180 on the circumference of the barrel 18. The strongback 24 is rigidly mounted to the barrel section 18 and has an aperture from which the cargo hook cable 16 is attached. A tapered capture skirt 26 is connected to the bottom of cylindrical barrel section 18 to guide torpedo 12 into the barrel 18 during the capture operation.

The operation of the device will be described with reference to the figures. In use the recovery system 10 is attached to the helicopter by means of a foot cargo hook cable 16 attached to the strongback 24 and the helicopters cargo hook. In addition the helicopters rescue hoist cable 14 is attached to the lifting ring 20 on the barrel section 18. The recovery system 10 is flown to the recovery site suspended at the end of the cargo hook cable 16 with a small amount of tension in the rescue hoist cable 14. As shown in FIG. 1 for capture the system 10 is suspended vertically from the rescue hoist cable 14 with the bottom of the skirt 26 approximately 30 feet below the helicopter and approximately 2 to 4 feet above the water. In this position the cargo hook cable 16 is slack.

After the helicopter is maneuvered until the capturev skirt 26 is over torpedo 12, the system 10 is lowered over the torpedo as shown in FIG. 2. This is accomplished through a combination of lowering the rescue hoist cables 14 and dipping the helicopter.

Once the torpedo 12 is in the barrel section 18, the rescue hoist cable 14 is slacked off. The helicopter by lifting up and moving slightly aft with the cargo hook cable 16 rotates the system 10 and torpedo 12 to the horizontal position. The helicopter lifts the system 10 and torpedo 12 out of the water where the system 10 assumes a barrel 18 down attitude. Slack is then removed from the rescue hoist cable 14. The above is shown in FIGS. 3 and 4.

The torpedo is then flown at speeds up to 70 knots back on the end of the lines 14 and 16 to the landing site. The rescue hoist cable 14 is used only to control the attitude of the cage once it is positioned over the torpedo 12 and to control the nose down attitude during flight to the landing area. At the landing site the helicopter hovers and slowly lowers the system 10 and torpedo 12 to the ground setting them down on the landing frame 22 of the system 10. The above is shown in FIG. 5.

A ground crewman detaches rescue hoist cable 14 from the system 10. The helicopter releases cargo hook cable 16 and reels in rescue hoist cable 14. Ground crewmen detach the skirt 26 from the barrel 18 by removing attaching bolts and walking the skirt 26 off the torpedo 12. When the skirt 26 is removed the center of gravity of the torpedo 12 is exposed. A lifting strap is placed around the center of gravity. A crane then lifts the torpedo approximately 2 feet off the ground. The

barrel 18 is then walked off the torpedo. Once the torpedo has been secured system 10 is reassembled for the next torpedo capture and recovery.

There has therefore been described a method of cap- 5 turing a torpedo l2 and a system utilized in this capture. The system is extremely simple, has no moving cated weapons.

Itwill be understood that various changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to. explain the nature of the invention, may be made by those skilled in the art within the principle and scope of i the invention as expressed in the appended claims.

What is claimed is:

1. A diverless helicopter weapon recovery device for vertical floating torpedoes comprising:

a barrel enclosed at one end and open at the other end;

a skirt connected to said barrel in axial alignment with said barrel, said skirt further comprises a first hoop having a first predetermined circumference connected to said barrel, a second hoop having a second predetermined circumference larger than said first predetermined circumference located at the end of said skirt opposite said first hoop and a plurality of bars connecting said first and second hoops;

a landing frame connected to said barrel;

a strongback connected to said barrel at a location diametrically opposed to said landing frame; and

connecting means connected to the device and adapted to be connected to lines for raising and lowering and changing the axial direction of the device; said connecting means further comprises a lifting ring connected to said one end of said barrel, an arm having an aperture, said arm located on said strongback, and first and second lines connected respectively to said lifting ring and said aperture.

2. A method of retrieving a vertical floating torpedo comprising the steps of:

lowering a framed cage in the vertical position from a helicopter over said vertical floating torpedo;

enclosing said torpedo with said framed cage in the water; v repositioning said framed cage to a horizontal position by means of slackening a line connected to the enclosed end of said cage and raising a line connected intermediate the ends of said cage; and raising said framed cage out of the water.

3. A method of retrieving a vertical floating torpedo according to claim 2 comprising the additional steps of:

positioning said helicopter over a landing surface;

lowering said framed cage onto said landing surface;

and removing said torpedo from said framed cage.

protection for the delicate parts of todays sophisti- 

1. A diverless helicopter weapon recovery device for vertical floating torpedoes comprising: a barrel enclosed at one end and open at the other end; a skirt connected to said barrel in axial alignment with said barrel, said skirt further comprises a first hoop having a first predetermined circumference connected to said barrel, a second hoop having a second predetermined circumference larger than said first predetermined circumference located at the end of said skirt opposite said first hoop and a plurality of bars connecting said first and second hoops; a landing frame connected to said barrel; a strongback connected to said barrel at a location diametrically opposed to said landing frame; and connecting means connected to the device and adapted to be connected to lines for raising and lowering and changing the axial direction of the device; said connecting means further comprises a lifting ring connected to said one end of said barrel, an arm having an aperture, said arm located on said strongback, and first and second lines connected respectively to said lifting ring and said aperture.
 2. A method of retrieving a vertical floating torpedo comprising the steps of: lowering a framed cage in the vertical position from a helicopter over said vertical floating torpedo; enclosing said torpedo with said framed cage in the water; repositioning said framed cage to a horizontal position by means of slackening a line connected to the enclosed end of said cage and raising a line connected intermediate the ends of said cage; and raising said framed cage out of the water.
 3. A method of retrieving a vertical floating torpedo according to claim 2 comprising the additional steps of: positioning said helicopter over a landing surface; lowering said framed cage onto said landing surface; and removing said torpedo from said framed cage. 